The questions do matter, because what you get depends on what film, what its exposure was, and the developer to be used. Change any of those and you get a different result. There are too many variables to answer the question "what will the result be?". The choice of film, developer and how long to process is always dependant on what the desired result is.
That said, some very general prediction is possible. For example, if you were to choose a developer like Rodinal diluted 1:4, with a film like Tri-X under exposed by 3 stops and 5 times what might be called a "normal" time, I would expect extremely contrasty grainy negatives. Rodinal is supplied as a concentrate and is meant to be used a dilutions more like 1:25 or 1:50, and even 1:100, at 1:4 it would be a very strong brew.
OTH, a developer like Xtol is mixed from powder to a working solution and is meant to be used straight or 1:1, at 1:4 there would barely be enough develping agent to function. And developing for 5 times a "normal' time might very well not be long enough. Offhand I would expect thin negatives with low contrast.